تخلفات ساختمانی و تغییرات فضایی-کالبدی در مناطق کلان‌شهر تهران

وقوع تخلفات ساختمانی یکی از مهم ترین آسیب های توسعه ی فضاییکالبدی کلان شهر تهران در دو دهه ی اخیر بوده است. این پژوهش در پاسخ به این سوال اساسی صورت گرفت که وضعیت و زمینه های وقوع تخلفات ساختمانی و تغییرات فضاییکالبدی در مناطق کلان شهر تهران در دهه های 1370 و 1380 چه بوده است؟ این پژوهش از نوع شناختی است که به روش کیفی و تفسیری انجام شده است. هدف پژوهش شناخت، توصیف و تفسیر وضعیت و زمینه های وقوع تخلفات ساختمانی و تغییرات فضاییکالبدی در مناطق کلان شهر تهران است. جامعه ی آماری این پژوهش، کل ساخت و سازها در محدوده ی مناطق بیست و دوگانه کلان شهر تهران است. داده ها و اطلاعات مورد نیاز این پژوهش به روش مطالعات کتابخانه ای و اسنادی جمع آوری شده است. برای توصیف و تفسیر داده ها و اطلاعات این پژوهش از آمار توصیفی و برای نمایش یافته های آن از سیستم اطلاعات جغرافیایی (gis) استفاده شده است. بر اساس یافته های این پژوهش، تخلفات ساختمانی بسیاری در دهه های 1370 و 1380 در کلان شهر تهران به وقوع پیوسته است، به طوری که به ازای هر پروانه ساختمانی صادره در این کلان شهر در سال های 1376 تا 1387، حدود 5/3 مورد تخلف ساختمانی در دبیرخانه ی کمیسیون های ماده ی صد قانون شهرداری به ثبت رسیده است. بیشترین حجم (مساحت) این تخلفات در این دوره در مناطق یک تا پنج کلان شهر تهران رخ داده است که ارزش و تراکم مازاد ساختمانی بیشتر دارد. کسب درآمد و فروش تراکم مازاد ساختمانی مهم ترین زمینه های ارتکاب این تخلفات در این کلان شهر است. مغایرت گسترش سطح و سرانه بنای مسکونی و کاربری های تجاری و نظامی و تعداد جمعیت با طرح جامع از مهم ترین تغییرات فضاییکالبدی در مناطق کلان شهر تهران در این دوره است.

Building Violations and Spatial-Physical Changes in Districts of Tehran Metropolis

Illegal sale of extra building density (footages) and building violations all are being considered as the most important measures regarding urban management rent issues in Tehran, between 19912001. This in turn, intensifies the occurrence of building violations and instability regarding to Tehran rsquo;s spatial organization during the mentioned decade. This study aims to investigate the type, rate and spatial distribution of building violations and spatialphysical changes in districts of Tehran metropolis. The objective of this paper is to identify and explain the types of urban management functions and their resulting consequences in Tehran metropolis. The distribution pattern of building violations and some of their impacts are the major outcome of this research. This research based on its objective, possesses applied nature at strategic level. This study is based on spatialstructural and analytical approach. The under study area are all constructions in 22 districts of Tehran metropolis. It further supports the application of documentation. Data analysis demands descriptive statistic as well as GIS technique. This study suggests that 59% of all the issued construction permissions are associated with zone 15 followed by 67% which pertains to zones 17 between 19932002. These northern zones possess large holdings, good location, comparative advantage and very beneficial vertical density. About 117028 building licenses contain extra building footage problems. Total area of these violations occurrences has been amounted up to 32710210 meters. The distribution of the extra building footages associated with different zones represents a sharp but regular gradient with northsouth direction. Moreover, this study suggests most of the governmental institutions committed violations associated with illegal land possessions as well as construction of illegal land uses in the area of public lands during 1990 decade. In addition, 249 illegal constructions pertaining to public institutions were identified by 2002 out of which 137 (55%) were visited by Tehran's municipalities. The statistics associated with Tehran's building violations which referred to variance number 1 of 100 municipality law represents a high magnitude and level of violations occurrence during 2000 decade. The total area deal with these building violations inspected by these commissions has been amounted to be 2810559 and 1565644 square meters in 2001 and 2008 respectively. However, some of these types of violations informally resolved without ever referred to this corresponding municipality commissions. Most of these violations are associated with land use changes (56.98%). This is followed by violations pertaining to extra density footages. It is argued that 3.5 violation cases registered against each issued construction license between 19972008 in Tehran metropolis. Generally, the issuances of building permits and sale of extra construction density and footages were dealt with market demand and geared toward gaining its resulting rents. These measures and actions were contradicted with Tehran's master plan principles. These violations possess a sharp gradient with northsouth directions in Tehran's south and north economicsocial basins. These activities are harmful to public interests and simultaneously very beneficial to very small inclusive private group which possess capital and lands. This in turn, is associated with lack of a master plan and subsequent spatial equalization, imbalanced land uses per capita and services and cons equally. Tehran's unsustainable physical development, For instance, Tehran's residential per capita in 1991, 1996, and 2001 has been amounted to be 20.35, 22.51 and 23.88 square meters respectively. This amount is associated with 17.37% growth rate unit during 1990 decade. However, Tehran's residential per capita in 1996 and 2001 have been underestimated and amounted to be 17.8 and 12.8% respectively compared with 1995 estimation (27.39 square meters). Tehran's existing commercial per capita in 2001 (2.05 square meters) compared with previous estimation of 1996 (0.87 square meters) shows 136.44% growth. This has been resulted from change in existing residential unit in central part of Tehran. Tehran's military per capita land use in 2001 (7.50 square meters) compared with the previous estimation of 2006 (1.5 square meters) shows 400.87% growth as well.